Liquid metering device and process for dispensing a liquid cleaning solution

ABSTRACT

A liquid metering system for a commercial or industrial laundry operation includes a dosing tank supported by a sensor that can measure the volume of the fluid passed there though with a magnetic field. The flowrate or volume can be used to determine the amount of a cleaning solution dispensed to a plurality of washing machines. A plurality of valves, as well as the sensor and pump, may be controlled by a controller which opens and closes the valves and operates the pump, to control the dispensing of various cleaning solutions to the washing machines.

FIELD OF THE INVENTION

The present invention relates to a liquid metering, measuring, and dispensing device and particularly to such devices for use in industrial or commercial laundry facilities.

BACKGROUND OF THE INVENTION

Large capacity industrial and commercial laundry facilities utilize washing machines having capacities on the order of 100 lbs. or more of laundry. Depending upon the type of laundry, different types and amounts of detergent, chemicals, and cleaning solutions are used during different stages in the washing operation. Since the sizes of washing machines and the sizes of individual loads of laundry can vary throughout a commercial washing facility and from load to load, it is desirable to have an automated system for dispensing the correct amount of detergent and cleaning solutions for each system and each load.

Known systems for regulating the various chemicals and liquids used in commercial laundry facilities rely upon in-line flowmeters to measure the flowrate of a given liquid through a given conduit. When the flowrate is known, the total amount of liquid dispensed by the system can be controlled by regulating the duration of the flow.

Many known systems utilize one or more flowmeters that rely on a gear, or another similar moving element, in order to determine the flowrate of the liquid passing there through. More specifically, as the liquid passes the gear in the flowmeter, the gear will rotate. The amount of liquid can then be determined based upon the rotations of the gear. These flowmeters that rely on the liquid to physically move some element, like the gear, are susceptible to interference from laminar flow, changing viscosities of liquids, and solids in the liquid.

In contrast to the flowmeters with moving parts, U.S. Pat. No. 5,590,686 discloses a system that uses a magnetic flowmeter in order to provide accurate and effective liquid chemical delivery. The magnetic flowmeter does not rely on moving parts in the flow path of the liquid to determine a flow rate, and thus avoids one or more of the drawbacks discussed above in regards to these types of flowmeters. However, such a device disposes a flowmeter upstream of the pump, which can lead to problems with flow direction depending on the type of pump. Furthermore, if the liquid in the flowmeter is not conductive, the flowmeter will not be able to measure the volume of liquid passing there though.

Therefore, there remains a need for a liquid metering device which utilize a flowmeter that does not utilize moving parts to determine a flowrate that is less susceptible to liquid movements from pumps. Furthermore, there is a need that such a device be configured to determine the amount of a non-conductive liquid.

Thus, one of the problems to be addressed is to provide a liquid metering device which includes a flowmeter that does not utilize moving parts to determine a flowrate and can determine an amount of nonconductive cleaning solution to be dispensed.

SUMMARY OF THE INVENTION

A liquid dispensing device and a process for dispensing a liquid cleaning solution have been invented.

In a first aspect of the present invention, the present invention may be broadly characterized as providing a liquid metering device for dispensing a cleaning solution in a laundry operation. In one or more embodiments the device comprises: a first supply tank containing a first cleaning solution; a pump configured to withdraw the first cleaning solution from the first supply tank and provide an output stream having a flowrate; a sensor in communication with the output stream and configured to utilize a magnetic field of the output stream to measure a volume of the output stream passing through the sensor; and, a controller in communication with the sensor and configured to adjust a flowrate of the first cleaning solution based upon the volume of the output stream that has passed though the sensor.

In some embodiments of the present invention, the device further comprises a second supply tank containing a second cleaning solution. The pump is configured to withdraw the second cleaning solution from the second supply tank. It is contemplated that the device further comprises a manifold configured to receive the first cleaning solution and the second cleaning solution and to provide a stream to the pump.

In some embodiments of the present invention, the device further comprises a valve in communication with the controller and in communication with the output stream from the pump and being associated with a line to first washer. It is contemplated that the device includes a second valve in communication with the controller and in communication with the output stream from the pump and being associated with a line to a second washer.

In various embodiments of the present invention, the device further comprises a plurality of valves. Each valve may be in electrical communication with the controller and may be in fluid communication with the output stream from the pump. It is contemplated that each valve is associated with a line to a washer.

In one or more embodiments of the present invention, the device further comprises a plurality of supply tanks each containing a cleaning solution and a manifold configured to receive the cleaning solutions and to provide a stream to the pump. The pump may be configured to withdraw the cleaning solutions from the supply tanks. It is contemplated that the device also comprises a plurality of lines, each line configured to pass a cleaning solution from a supply tank to the manifold. It is further contemplated that at least one line from the plurality of lines includes a valve, and the valve is in communication with the controller.

In a second aspect of the present invention, the present invention may be generally characterized as providing a process for controlling the dispensing of a liquid cleaning solution by: withdrawing a cleaning solution from a supply tank; passing a liquid output stream from a pump to a washer, the liquid output stream comprising at least the cleaning solution; and, determining a volume of the liquid output stream of the pump with a sensor by passing the liquid output stream of the pump though a magnetic field in order to determine a dispensed amount of the cleaning solution to be passed from the pump to the washer.

In some embodiments of the present invention, the process includes comparing the dispensed amount to a desired amount. It is contemplated that the process includes reducing a flowrate of the cleaning solution to the washer when the dispensed amount is at least equal to the desired amount. It is also contemplated that the process includes continuously comparing the dispensed amount to the desired amount until the dispensed amount is at least equal to the desired amount, and controlling a valve in a line containing the cleaning solution stream when the dispensed amount is at least equal to the desired amount.

In some embodiments of the present invention, the process includes controlling a valve based upon the dispensed amount. The valve may be disposed in a line containing the liquid output stream.

In one or more embodiments of the present invention, the process includes controlling a plurality of valves based upon the dispensed amount. Each valve may be disposed in a line containing the liquid output stream and each line may be arranged between the pump and a washer. It is contemplated that the valves are controlled by allowing the liquid output stream to pass there though until the dispensed amount reaches a desired amount, and then closing the valves to prevent the liquid output stream to pass there though. It is further contemplated that the process includes opening the valves to allow the liquid output stream to pass there though.

In at least one embodiment of the present invention, the process includes withdrawing a second cleaning solution from a second supply tank, and, determining a second volume of the liquid output stream of the pump with the sensor by passing the liquid output stream of the pump though a magnetic field in order to determine a dispensed amount of the second cleaning solution to be passed from the pump to the washer. It is contemplated that the process includes passing the second cleaning solution to a plurality of washing machines via a plurality of lines. It is still further contemplated that each line is associated with a valve and the valves are in communication with a controller. The controller is in communication with the sensor.

Additional aspects, embodiments, and details of the invention, all of which may be combinable in any manner, are set forth in the following detailed description of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

One or more exemplary embodiments of the present invention will be described below in conjunction with the following drawing FIGURE, in which:

The FIGURE shows a schematic diagram of a device according to one or more embodiments of the present invention, and which may be used in one or more embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

As mentioned above, a liquid dispensing device and a process for dispensing a liquid cleaning solution have been invented in which an electromagnetic flowmeter measures the flowrate of a conductive liquid passing there though is used. The electromagnetic flowmeter does not include elements, such as a gear, or the like, in the path of the liquid, but instead measures the flowrate of the liquid by using a magnetic field. Therefore, the electromagnetic flowmeter will not be subject to interference form laminar flow, or be affected by the different viscosities of fluids passing there through. In the various embodiments, the flowmeter is disposed to measure the output stream of the pump so as to avoid miscalculation or incorrect readings caused by backflow.

With these general principles in mind, one or more embodiments of the present invention will be described with the understanding that the following description is not intended to be limiting.

With reference to the FIGURE, a liquid metering device 10, or dispensing device, for a laundry operation or process is shown which includes at least one, and more preferably a plurality of, supply tanks 12 a-12 n. The supply tanks 12 a-12 n each contain a cleaning solution, such that the liquid metering device 10 preferably includes a plurality of different cleaning solutions. As used herein, the term “cleaning solution” shall refer to any liquid pumped and distributed by the liquid metering device 10 without regard to its specific composition or ultimate purpose in the cleaning/laundering process, including for example, bleaches, rinses, water, flush fluids, sours, softeners, sanitizers, acids, alkalis, detergents, to name a few.

A stream of each cleaning solution may be withdrawn from each supply tanks 12 a-12 n via a line 14 a-14 n. As shown in the drawing, each line 14 a-14 n may include a valve 16 a-16 n for controlling a flow of the cleaning solution there through. The cleaning solutions being withdrawn from the supply tanks 12 a-12 n may be passed to, for example, a manifold 18. Although not depicted as such, the valves 16 a-16 n for the lines 14 a-14 n may be formed as a part of the manifold 18.

The valves 16 a-16 n may be in communication with a controller 20 which opens and closes the valves 16 a-16 n to control the dispensing of the various cleaning solutions. In the FIGURE, the communication between various elements are shown in dashed lines.

The controller 20 may include a pre-programmed logic controller having an electronic computer or central processor which, among other functions, receives information from various components of the device 10, processes such information, and provides control signals to various components of the device 10 and to control the operation of the device 10. An input device 22, such as a keyboard, key pad, touch screen display, may be used to input control information, for example, flow time, sequence, etc., or instructions to controller 20, which uses such information in controlling various other components of the device 10. A display screen 24 is provided to give a visual display of the information imputed to controller 20 and/or to display the operational status of various other components of device 10 and/or to provide a visual warning of an alarm condition existing in the device 10. It should be appreciated that the input device 22 and display screen 24 may be the same component, or may occupy different portions of the same component.

Returning to the FIGURE, a pump 26 is used to withdraw the cleaning solutions from the supply tanks 12 a-12 n and provide an output stream 28. In at least one embodiment, the pump 26 comprises a diaphragm pump, based at least in part upon the relatively low cost, long life, and good reliability associated with same. Those skilled in the art will readily appreciate that other types of pumps could also be used without departing from the spirit and scope of the present invention.

A line 30 may be used to pass each of the various cleaning solutions from the manifold 18 to the pump 26. As will be appreciated the output stream 28 from the pump 26 will change depending on the cleaning solution(s) withdrawn from the storage tank(s) 12 a-12 n and during a particular cycle or stage of a laundry process. The operation of the pump 26 is preferably based upon one or more signals from the controller 20, accordingly the pump 26 and the controller 20 are typically in communication.

In various processes, the output stream 28 from the pump 26 is passed to one or more washers (i.e., washing machines) 32 a-32 n. In a preferred embodiment, as shown in the FIGURE, the output stream 28 of the pump 26 is first passed to a distribution manifold 34. The distribution manifold 34 is associated with a plurality of outlet valves 36 a-36 n, each associated with a line 38 a-38 n and each being configured to open (to allow the flow of fluids to an individual washer 32 a-32 n) and to close (to stop the flow of fluids). The outlet valves 36 a-36 n may be disposed in the distribution manifold 34, or in the lines 38 a-38 n, or both. Each outlet valve 36 a-36 n may be in communication with the controller 20 which controls the opening and closing of the outlet valves 36 a-36 n. Additional valves (not shown) may be disposed in the individual lines 38 a-38 n between the distribution manifold 34 and the washing machines 32 a-32 n, and these valves may be in communication with the controller 20.

In order to determine the amount of a particular cleaning solution that has been delivered to the washing machines 32 a-32 n, at least one line for the output stream 38 includes a sensor 40 in fluid communication with the output stream 38. The sensor 40 utilizes a magnetic field to determine an amount of fluid (i.e., a volume) that is passing there though and/or a flowrate of the fluid passing there though.

Preferably, the sensor 40 comprises an electromagnetic flowmeter such as the LFE Series of flowmeters from SMC Corporation Tokyo, Japan (see, U.S. Pat. No. 2014/0298920). The electromagnetic flowmeter may be used to measure the electromotive force generated by the conductive fluid passing there through (i.e., Faraday's law of induction). The measured electromotive force may be used to calculate the volume flow (units/time). Another contemplated sensor 40 is disclosed in U.S. Pat. Pub. No. 2014/0366641. Based upon the measured flowrate (and a known or measured amount of time), the actual volume of the fluid that has passed through the sensor 40 can be determined. Depending upon the number of washing machines 32 a-32 n in use, the amount of dispensed cleaning solution to be dispensed may be accurately determined and controlled. The sensor 40 is in communication with the controller 20.

By disposing the sensor 40 downstream of the pump 26, the sensor 40 will be less likely to be affected by any pulsating flows or back flows created by certain pumps. Furthermore, by disposing the sensor 40 downstream of the pump 26, the length of the lines 14 a-14 n to the supply tanks 12 a-12 n can be made shorter which allows more suction of the cleaning solutions. The amount of suction needed to withdraw the different cleaning solutions may change depending on the viscosity of the different liquids. Additionally, by positioning the sensor 40 downstream of the pump 26, the number of points where air leaks can occur will be lowered. The air leaks will affect the sensor 40 and reduce flowrates and suction. Furthermore, by utilizing the sensor 40 downstream of the pump 26, the device 10 can be used with nonconductive liquids.

More specifically, with the sensor 40 on the outlet side of the pump 25, the distance between the sensor 40 and the supply tanks 12 a-12 n can be made greater. The lines in the device 10 may be filled with a conductive cleaning solution, such as water, so that when the pump 26 begins operation, it will move the conductive cleaning solution through the sensor 40. At the same time another cleaning solution, in this case a nonconductive cleaning solution may be drawn from one of the supply tanks 12 a-12 n. By measuring the amount of conductive cleaning solution that is being passed through the sensor 40, the amount of nonconductive cleaning solution that is withdrawn from the supply tanks 12 a-12 n (and which may not have reached the sensor 40) can be accurately determined. Thus, the sensor 40 may be used to accurately measure an amount of cleaning solution to be dispensed even if that particular cleaning solution is nonconductive.

In an exemplary use of the device 10 in typical laundry process, the controller 20 will open one of the valves 16 a-16 n for a first cleaning solution and the pump 26 will draw the first cleaning solution through the appropriate line 14 a-14 n, through the manifold 18, through the pump 26, and through the sensor 40. The cleaning solution will then pass though the distribution manifold 34, passed the outlet valves 36 a-38 n which are opened and to the washing machines 32 a-32 n being operated. The controller 20 may automatically determine which washing machines 32 a-32 n are in use (and thus which outlet valves 36 a-36 n in the distribution manifold 34 should be opened), or the information could be manually entered by a user at the start of the laundry process, for example via the input device 22.

The sensor 40 will communicate with the controller 20 so that when the desired amount of first cleaning solution has been passed to the washing machines 32 a-32 n (which can be determined by the sensor 40 itself, or by the controller 20), the controller 20 may determine the amount of first clean solution that has been withdrawn (and that will be dispensed) and adjust the amount of the first cleaning solution that is being withdrawn, for example, by closing the valve 16 a-16 n associated with the first cleaning solution. The sensor 40 may continuously measure or relay that amount of fluid passed there though, for example, every millisecond, every one second, or ant any another appropriate time interval, allowing the controller 20 (or the sensor 40 itself) to continuously compare the dispensed amount with the desired amount. Alternatively, the controller 20 (or the sensor 40 itself) may simply act when the dispensed amount at least equals the desired amount

Once the desired amount of the first cleaning solution has been withdrawn (and potentially dispensed to the washers 32 a-32 n), a second valve 16 a-16 b, associated with a second cleaning solution, may then be opened, and the process would continue as with the first cleaning solution until the desired amount of the second cleaning solution has been dispensed (or at least withdrawn). Based upon the stage of the process, the controller 20 may wait a certain amount of time between dispensing the various cleaning solutions.

A third cleaning solution, and so on and so forth, may be withdrawn until the process has completed. Additionally, as mentioned above, if one of the cleaning solutions is nonconductive, the sensor 40 and the controller 20 may measure any amount of conductive cleaning solution that is displaced while the nonconductive cleaning solution is being withdrawn. This will allow the device 10 to ensure that a desired amount of nonconductive cleaning solution is dispensed.

In some instances in may be desirable to mix two or more cleaning solutions, so the controller 20 may open two or more valves 16 a-16 b to create a combined cleaning solution.

Additionally, for some stages of the process, the sensor may not measure the cleaning solution passing through the sensor 40, for example, if the cleaning solution comprises water, and it is not necessary to measure and accurately meter the water being passed to the washer 32 a-32 n. However, in some instances it may also be desired to measure the amount of water, for example, in order to determine an amount of nonconductive cleaning solution.

Finally, one of ordinary skill in the art will appreciate that the device 10 can be run or programmed to run in a variety of different processes and the present invention is not limited to any particular laundry process.

In view of the foregoing, the device 10 is operable to meter and dispense a desired amount of at least one cleaning solution by measuring the amount of fluid outputted by the pump 26. The sensor 40 used in the device 10 does not interfere with the flow of the fluids there though. Additionally, since the sensor 40 is disposed downstream of the pump 26, a more accurate and reliable determination of the amount of dispensed liquid can be made, including for nonconductive cleaning solutions.

It should be appreciated and understood by those of ordinary skill in the art that various other components such as valves, pumps, heaters, filters, coolers, etc. were not shown in the drawings as it is believed that the specifics of same are well within the knowledge of those of ordinary skill in the art and a description of same is not necessary for practicing or understanding the embodiments of the present invention.

While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents. 

What is claimed is:
 1. A liquid metering device for dispensing a cleaning solution in a laundry operation, the device comprising: a first supply tank containing a first cleaning solution; a pump configured to withdraw the first cleaning solution from the first supply tank and provide an output stream having a flowrate; a sensor in communication with the output stream and configured to utilize a magnetic field of the output stream to measure a volume of the output stream passing through the sensor; a controller in communication with the sensor and configured to adjust a flowrate of the first cleaning solution based upon the volume of the output stream that has passed though the sensor.
 2. The device of claim 1 further comprising: a second supply tank containing a second cleaning solution, wherein the pump is configured to withdraw the second cleaning solution from the second supply tank.
 3. The device of claim 2 further comprising: a manifold configured to receive the first cleaning solution and the second cleaning solution and to provide a stream to the pump.
 4. The device of claim 1 further comprising: a valve in communication with the controller and in communication with the output stream from the pump and being associated with a line to first washer.
 5. The device of claim 4 further comprising: a second valve in communication with the controller and in communication with the output stream from the pump and being associated with a line to a second washer.
 6. The device of claim 1 further comprising: a plurality of valves, each valve in communication with the controller and in communication with the output stream from the pump and each valve associated with a line to a washer.
 7. The device of claim 6 further comprising: a plurality of supply tanks each containing a cleaning solution; and, a manifold configured to receive the cleaning solutions and to provide a stream to the pump, wherein the pump is configured to withdraw the cleaning solutions from the supply tanks.
 8. The device of claim 7 further comprising: a plurality of lines, each line configured to pass a cleaning solution from a supply tank to the manifold.
 9. The device of claim 8 wherein at least one line from the plurality of lines includes a valve, and wherein the valve is in communication with the controller.
 10. A process for controlling the dispensing of a liquid cleaning solution, the process comprising: withdrawing a cleaning solution from a supply tank; passing a liquid output stream from a pump to a washer, the liquid output stream comprising at least the cleaning solution; and, determining a volume of the liquid output stream of the pump with a sensor by passing the liquid output stream of the pump though a magnetic field in order to determine a dispensed amount of the cleaning solution to be passed from the pump to the washer.
 11. The process of claim 10 further comprising: comparing the dispensed amount to a desired amount.
 12. The process of claim 11 further comprising: reducing a flowrate of the cleaning solution to the washer when the dispensed amount is at least equal to the desired amount.
 13. The process of claim 11 further comprising: continuously comparing the dispensed amount to the desired amount until the dispensed amount is at least equal to the desired amount; and, controlling a valve in a line containing the cleaning solution stream when the dispensed amount is at least equal to the desired amount.
 14. The process of claim 10 further comprising: controlling a valve based upon the dispensed amount, the valve disposed in a line containing the liquid output stream.
 15. The process of claim 10 further comprising: controlling a plurality of valves based upon the dispensed amount, each valve disposed in a line containing the liquid output stream and each line arranged between the pump and a washer.
 16. The process of claim 15 wherein the valves are controlled by allowing the liquid output stream to pass there though until the dispensed amount reaches a desired amount, and then closing the valves to prevent the liquid output stream to pass there though.
 17. The process of claim 16 further comprising: opening the valves to allow the liquid output stream to pass there though.
 18. The process of claim 10 further comprising: withdrawing a second cleaning solution from a second supply tank; and, determining a second volume of the liquid output stream of the pump with the sensor by passing the liquid output stream of the pump though a magnetic field in order to determine a dispensed amount of the second cleaning solution to be passed from the pump to the washer.
 19. The process of claim 18 further comprising: passing the second cleaning solution to a plurality of washing machines via a plurality of lines.
 20. The process of claim 19 wherein each line is associated with a valve and wherein the valves are in communication with a controller, the controller being in communication with the sensor. 